The present invention relates to a device which is suitable for rendering harmless the nonreusable cannulae of a syringe.
Due to the danger of infection, the majority of syringes now in use are designed for one time use only. Such syringes consist of a plastic needle body over which is slid the cannula that comprises both a metal tube and a plastic body forming the cannula head. In order to prevent the repeated use of such cannulae and the attendant spread of infection, one prior art method involves bending the cannula or its metal tube out of its normally straight shape into a bent shape in order to indicate that the cannula has already been used. After being bent out of shape, the cannulae are, more often than not, discarded in the internal garbage system. In another conventional disposal method, the still straight cannulae, after having been used once, are tossed into special containers having a pail-like jacket. After having been filled to a suitable level with used cannulae, the container is filled to the top with liquid plaster. Thus covered, the syringes are carried in the special container to the waste disposal site.
Because the method of manually bending the syringes entails both the risk of injury and contact with infected liquids, a method is disclosed in EP 0 136 392 B1 by means of which cannulae can be deformed with the aid of an electric current. Provided for this purpose is an apparatus of the type in which arranged beneath the insertion opening are two spring-mounted electrodes which, while not directly contacting each other, can be connected together via the metal tube of the cannula in a manner that permits an electrical current to flow through the metal tube of the cannula. The shape of the insertion opening permits the cannula, together with its plastic head, to be pushed inside the apparatus. A laterally-oriented longitudinal extension of the insert opening permits the head to catch when slid laterally in the direction of the longitudinal extension. A slanted guide element located on the underside of the longitudinal extension ensures the separation of the cannula from the syringe body, and allows the entire cannula together with its deformed metal tube, to fall into a drawer located inside the apparatus, the result of which being that the user has left in his hand only the syringe body, which is now open toward the bottom.